Intercostal pump

ABSTRACT

An intercostal-pump based fluid management system, as described herein, comprises an intercostal pump that is, generally, a resiliently flexible bulb having an inlet and an outlet. The inlet is attached to a first tube that extends from the intercostal pump to a first area of a patient&#39;s body, for example, the patient&#39;s pleural cavity. The outlet is connected to a second tube that extends from the intercostal pump to a second area of a patient&#39;s body, for example, the patient&#39;s peritoneal cavity. In use, the intercostal pump is placed between a first rib and a second rib in a patient. The intercostal pump operates by being successively compressed and decompressed between the first and second ribs as the patient breaths.

RELATED APPLICATIONS

This application claims priority to U.S. patent application Ser. No.13/968,479 filed on Aug. 16, 2013, entitled “Systems and Methods forDraining Bodily Fluid via an Intercostal Pump,” which is incorporatedherein in its entirety. U.S. patent application Ser. No. 13/968,479claims priority to U.S. Provisional Patent Application Ser. No.61/684,101 filed Aug. 16, 2012, entitled “Systems and Methods forDraining Bodily Fluid via an Intercostal Pump,” which is alsoincorporated herein in its entirety.

BACKGROUND

A number of well-known techniques for draining bodily fluid involveutilizing a pump, in combination with a shunt or catheter, to drainfluid from one cavity within the human body to either another cavity orto a reservoir outside of the body. Such techniques may be utilized forpurposes including, for example, draining a patient's blood, urine,saliva, cerebrospinal fluid, peritoneal fluid, and/or pleural fluid,among other possibilities.

One common drainage-technique application is the drainage of pleuralfluid for the treatment of pleural effusions. Pleural fluid is normallya low-protein liquid that can be found in relatively small amounts(normally a few milliliters) in a patient's pleural cavity. The pleuralcavity is the space between the visceral pleura (i.e., the membranesurrounding each lung) and the parietal pleura (i.e., the membranelining the inside of the rib cage). Pleural fluid provides a lubricatingfunction during the breathing process and, normally, a patient's bodyconstantly produces and absorbs pleural fluid. However, under certainabnormal conditions, such as infection, inflammation, malignancy, heartfailure, liver failure, or kidney failure, among other conditions, thenet flow of pleural fluid within the pleural cavity becomes unbalancedresulting in the excess accumulation (e.g., on the order of liters) offluid in the pleural space.

Excess accumulation of pleural fluid is known as pleural effusion andmay cause the pathological compression of one or both lungs-resulting inconsiderable difficulty or prevention of the breathing process in eitheror both lungs. Pleural effusion may lead to, for example, dyspnea,shortness of breath, chest pain, and/or chronic cough, greatlycompromising a patient's quality of life.

Currently, pleural effusions affect approximately 1.4 million newpatients each year. Over 200,000 of such pleural effusions result frommalignancy and are seriously dangerous to the patients' health. Morethan one half of those patients with malignant pleural effusions havesymptoms resulting directly from their effusion.

One treatment option for recurrent, symptomatic pleural effusions isrepeated therapeutic thoracentesis. Thoracentesis involves passing aneedle and catheter apparatus into the pleural cavity, at which pointthe needle is removed, leaving the catheter in the pleural space. Thecatheter remains in place and, thereby, acts as a drainage tube thatleads the excess pleural fluid to a collection reservoir outside of thebody. This procedure typically improves symptoms significantly.Unfortunately, malignant effusions are likely to recur and, due topatients' delays in notifying their physician that their symptoms havereturned and delays in providing repeat thoracentesis, patients oftenspend a significant portion of their life with effusion-relatedsymptoms. Furthermore, thoracentesis is painful and uncomfortable, andis frequently accompanied by threatening or debilitating complications,such as pneumothorax (i.e., the collapse of the lung due to accumulationof air in the pleural cavity) in up to eleven percent of patients andsevere bleeding or infection in many others.

Another treatment option is chest-tube pleurodesis, which involves theobliteration of the pleural space by the instillation of a sclerosantagent via a chest tube. In this approach, a chest tube is inserted intothe patient under moderate sedation or general anesthesia and thepleural fluid is drained, in a manner similar to the drainage achievedin thoracentesis. After drainage of the pleural effusion a sclerosingagent is instilled through the tube into the pleural cavity tocompletely coat the visceral and parietal membranes so that thesemembranes will permanently adhere to each other to close and eliminatethe pleural cavity. Chest-tube pleurodesis can sometimes lead tolong-term control of effusion-related symptoms. Unfortunately,chest-tube pleurodesis typically requires hospitalization for at leasttwo days and as many as seven days, can be quite painful, can lead tobreathing difficulties of it's own, and, in up to one third of patients,fails to provide relief of symptoms for more than a few weeks.

One variation of chest-tube pleurodesis is thoracoscopic pleurodesis,which involves the insertion of a telescope into the patient's chest byway of an intercostal incision on the patient's side. Pleural fluid isevacuated and a detailed inspection of the pleural space is undertakenso as to more discriminately apply sclerosant to regions of abnormality.In some cases, thoracoscopic pleurodesis can achieve better results thaneven chest-tube pleurodesis. Unfortunately, thoracoscopic pleurodesistypically requires hospitalization for four to seven days.

Yet another treatment option is chronic indwelling pleural catheters.Such indwelling catheters are placed in the patient permanently,allowing a patient to drain pleural fluid to an external reservoir on anintermittent, yet continual, basis. That is, while the pleural catheteris placed substantially inside the patient, the catheter also extendsoutside of the patient's body and may remain externally exposed forextended period of times. Chronic indwelling catheters have been shownto result in relatively high success rates in the management ofeffusion-related symptoms, and are associated with relatively shortpatient-hospital times of approximately one day. However, a considerablepercentage of patients, approximately eight percent, fall victim toinfection. Further, the patient is subject to the discomfort,irritation, and annoyance of an exposed indwelling catheter thattransmits fluid to an external reservoir.

Related to indwelling pleural catheters, pleuroperitoneal shunts providea permanent conduit between the pleural cavity and the peritonealcavity, or the abdomen, which allows fluid to move from the pleuralcavity to the peritoneal cavity, as opposed to an external reservoir.Once in the peritoneal cavity, the fluid is reabsorbed into the patientsblood steam through blood and lymph vessels located in the abdomen. Inpopular pleuroperitoneal shunts, the shunt has a pumping chamber thatmust be manually activated by the patient or caregiver to move thepleural fluid. The pleuroperitoneal shunt is tunneled under the skinfrom the chest to the abdomen with the pumping chamber lodged in asubcutaneous pocket overlying the costal margin, or lower edge, of therib cage. Pleuroperitoneal shunts, like chronic indwelling catheters,have been shown to result in relatively high success rates in themanagement of effusion-related symptoms, and are associated withrelatively short patient-hospital times of approximately one day.However, also like chronic indwelling catheters, a considerablepercentage of patients, approximately four percent, fall victim toinfection. Further drawbacks of conventional pleuroperitoneal shuntsinclude a relatively high rate of shunt-specific complications, such asclotting of fluid within the shunt, as well as the discomfort andinconvenience arising from manual activation of the pump by the patient.

OVERVIEW

Accordingly, there is a need for a novel technique of draining pleuralfluid that provides for a high rate of success in treating pleuraleffusions, and avoids high rates of infection and other complications,doesn't require lengthy patient-hospital times and/or repeated hospitalvisits, and avoids the inconvenience of both manually activated pumpsand external reservoirs. A fluid management system based on anintercostal pump, as described herein, provides for such a novel andbeneficial drainage technique.

An intercostal-pump based fluid management system, as described herein,comprises an intercostal pump that is, generally, a resiliently flexiblebulb having an inlet and an outlet. The inlet is attached to a firsttube that extends from the intercostal pump to a first area of apatient's body, for example, the patient's pleural cavity. The outlet isconnected to a second tube that extends from the intercostal pump to asecond area of a patient's body. The second area of the patients' bodymay be, for example, the patient's peritoneal cavity. Upon operation ofthe intercostal pump, fluid is transferred from the first area of thepatient's body to the second area.

In use, the intercostal pump is placed between a first rib and a secondrib in a patient. (Note that although the terms “first rib” and “secondrib” are used herein, it should be understood that such use does notnecessarily refer to any particular two ribs, e.g. the “first” and“second” ribs as typically referred to in anatomical contexts as the tworibs nearest a patients' skull.) The intercostal pump operates by beingsuccessively compressed and decompressed between the first and secondribs as the patient breaths. As the patient inhales, the patient's ribcage expands and the intercostal pump is decompressed. As the patientexhales, the patient's rib cage contracts and the intercostal pump iscompressed.

Use of an intercostal pump as described herein avoids certainshortcomings of known fluid drainage techniques. For instance, theintercostal pump operates to drain fluid regularly, continuously, andautomatically without requiring a patient to manually compress a pump byhand or requiring a patient to drain fluid external to the patient'sbody. Further, due to the continuous operation of the intercostal pump,improved performance may be achieved by decreasing the occurrence ofclotting observed in other fluid-drainage systems that may remaininactive for long periods of time.

BRIEF DESCRIPTION OF DRAWINGS

The invention disclosed herein will be more readily understood from areading of the specification with reference to the accompanying drawingsforming a part thereof, wherein:

FIGS. 1A, 1B, and 1C show a perspective view of an exemplaryintercostal-pump based fluid management system including an exemplaryintercostal pump and also including inlet and outlet catheters shortenedfor illustrative purposes;

FIG. 2 shows an embodiment of an exemplary intercostal-pump based fluidmanagement system implanted in a patient;

FIGS. 3A, 3B, and 3C show a cross-sectional schematic view of anexemplary intercostal-pump body;

FIGS. 4A and 4B show a focused view of an exemplary intercostal-pumpbased fluid management system placed between a patient's ribs, and theintercostal pump activated thereby; and

FIGS. 5A and 5B show exemplary methods for draining bodily fluid.

FIG. 6 shows a perspective view of an additional exemplaryintercostal-pump based fluid management system.

DETAILED DESCRIPTION

The apparatuses, systems, and methods described herein may be used forthe purposes of draining fluid from one cavity within the human body toanother cavity. More particularly, the apparatuses, systems, and methodsdescribed herein comprise an intercostal pump which provides a generalpumping function in an intercostal-pump based fluid management system.

For purposes of explanation, the disclosure herein includes a discussionof the use of an intercostal-pump based fluid management system for thepurposes of drainage of pleural fluid for the treatment of pleuraleffusions. However, it should be understood that such an application isbut one particular application of one particular embodiment of anintercostal-pump based fluid management system, and that otherembodiments and applications are certainly possible as well.

Also, for purposes of explanation, the disclosure herein describes anintercostal pump as part of a particular exemplary intercostal-pumpbased fluid management systems. However, it should be understood thatany such intercostal-pump based fluid management system disclosed hereinis but a particular embodiment of an intercostal-pump based fluidmanagement system that uses an intercostal pump as described herein, andthat other uses of an intercostal pump are certainly possible as well.

The intercostal-pump based fluid management system provides for regular,continuous, and automatic drainage of bodily fluid. Therefore, many ofthe disadvantages of other techniques for draining bodily fluid may beavoided.

1. INTERCOSTAL-PUMP BASED FLUID MANAGEMENT SYSTEM

FIGS. 1A, 1B, and 1C show a perspective view of an exemplaryintercostal-pump based fluid management system including an exemplaryintercostal pump and also including inlet and outlet catheters (thedepiction of which have been shortened in length for illustrativepurposes). It should be understood that FIGS. 1A, 1B, and 1C show anembodiment of an intercostal-pump based fluid management system forpurposes of explanation and that other embodiments are certainlypossible as well.

a. Intercostal-Pump Based Fluid Management System Generally

With reference to FIG. 1A, intercostal-pump based fluid managementsystem 100 comprises intercostal pump 110. Intercostal pump 110 is,generally, a resiliently flexible bulb enclosing an interior space andhaving an inlet 130 and an outlet 132. Intercostal pump 100 may be madeof any suitable material that allows for intercostal pump 100 to becompressed and then freely returned to its original state. For example,intercostal pump 110 may be a resiliently flexible bulb made ofpolyurethane, silicone, polyvinyl chloride, or latex rubber.

Although intercostal pump 110 is shown as a generally spherical, orovular, bulb, other configurations are certainly possible as well. Inshort, intercostal pump 110 may be any shape providing for suitablecompression/decompression and placement in an intercostal region. Inparticular, it may be desirable to conform, to some extent, intercostalpump 110, to the characteristics (i.e., shape and/or space) of aparticular intercostal region. In an embodiment, intercostal pump 110may comprise flexible silicone tubing. Intercostal pump 110 may takeother forms as well.

Intercostal pump 110 is discussed in greater detail below.

Intercostal-based fluid management system 100 also comprises a firsttube 120 and a second tube 122. Inlet 130 and outlet 132 communicatebetween the interior and the exterior of intercostal pump 110 and arecoupled to the first tube 120 and the second tube 122, respectively. Inother words, inlet 130 and outlet 132 are configured so as to providefor fluid communication between first tube 120 and second tube 122,respectively, and an interior space of intercostal pump 110.

With reference to FIG. 1B, first tube 120 comprises a tube-inlet end 150and a pump-inlet end 140. Generally, first tube 120 is configured sothat, when intercostal-based fluid management system 100 is in use,tube-inlet end 150 may be disposed in an area of a person's body fromwhich fluid is to be drained. On the other hand, pump-inlet end 140 iscoupled to inlet 130 of intercostal pump 110. Accordingly, the length offirst tube 120 may vary, as depicted by length extension 160.

Similarly, second tube 122 comprises a pump-outlet end 142 and atube-outlet end 152. Generally, second tube 122 is configured so that,when intercostal-based fluid management system 100 is in use,tube-outlet end 152 may be disposed in an area of a person's body towhich fluid is to be drained. On the other hand, pump-outlet end 142 iscoupled to outlet 132 of intercostal pump 110. Accordingly, the lengthof second tube 122 may vary, as depicted by length extension 162.

Although first tube 120 and second tube 122 are shown as entering intointercostal pump 110 in a substantially straight-forward manner, firsttube 120 and second tube 122 may be configured to enter intercostal pump110 at any desired angle. For example, it may be desirable for firsttube 120 and second tube 122 to enter and leave, respectively,intercostal pump 110 at ninety-degree angles so as to enable intercostalpump 110 to be situated in the intercostal region in a more advantageousmanner. It may be desirable for first tube 120 and second tube 122 toenter and leave at other angles as well.

With reference to FIG. 1C, first tube 120 may comprise one or morefluid-inlet perforations 170. Fluid-inlet perforations 170 may take theform of holes in the surface of first tube 120 allowing for the intakeof fluid into first tube 120 through not only tube-inlet end 150, butthrough fluid-inlet perforations 170 as well. Fluid-inlet perforations170 may improve the volume or efficiency of fluid intake into first tube120, and thereby, may improve the volume or efficiency of fluid drainedby intercostal-pump based fluid management system 110. Fluid-inletperforations 170 may be particularly advantageous as allowing foralternative fluid inlet locations in the event that tube-inlet end 150,or other perforations, become blocked due to, for example, clotting.

Second tube 122 may also include fluid-outlet perforations (notdepicted).

In order to prevent clogging, the fluid inlets or outlets, the first andsecond tubes, or any other aspect of inter-costal pump based fluidmanagement system 100 may be coated in anticoagulation factors. Forexample, the valves of intercostal pump 110 may be coated withanticoagulation factors. The presence of the anticoagulation factors mayreduce the amount of clotting that would otherwise occur if they werenot present. Examples of anticoagulation factors include tissueplasminogen activator, heparin, urokinase, streptokinase, and warfarin.Other examples of anticoagulation factors may exist as well.

b. Pleuroperitoneal Inter-Costal Pump Based Fluid Management System

With reference to FIG. 2, intercostal-pump based fluid management system100 is implanted in a patient 200, providing for drainage of fluid froma first area 220 to a second area 230 within the patient's body. In oneembodiment, as in the embodiment depicted in FIG. 2, fluid is drainedfrom a patient's pleural cavity to the patient's peritoneal cavity. Insuch an embodiment, therefore, first area 220 is the patient's pleuralcavity and second area 230 is the patient's peritoneal cavity.

In an embodiment, intercostal pump 110 is configured so that it may beplaced, at least partially, in the intercostal region between two ribs.In other words, when implanted, intercostal pump 110 extends throughoutthe patient's intercostal space, or at least a portion thereof.Accordingly, first tube 120, and correspondingly, pump inlet 130 (notdepicted), are disposed on the interior of the patient's rib cage. Onthe other hand, second tube 122, and correspondingly, pump outlet 132(not depicted), are disposed on the exterior of the patient's rib cage.In this way, upon breathing and the correspondingcompression/decompression of the rib cage, patient 200 willautomatically cause intercostal pump 110 to operate (i.e., “pump”). Theoperation of intercostal pump 110 is discussed further below.

c. Other Inter-Costal Pump Based Fluid Management Systems

A fluid management system that includes intercostal pump 110 may be usedfor draining fluid from and to various areas of a patient's body. Thatis, a fluid management system that includes the intercostal pumpdescribed herein is not limited to uses involving draining fluid from apatient's pleural cavity to the patient's peritoneal cavity.

One example of an alternative use of a fluid management system thatincorporates the intercostal pump described herein is draining fluidfrom a patient's cerebrospinal region. According to this exemplaryalternative use, tube 120 may be configured to extend from intercostalpump 110 to the patient's cerebrospinal region such that tube-inlet end150 may be disposed in the patient's cerebrospinal region. In this way,excess cerebrospinal fluid may be drained.

Another example of an alternative use of a fluid management system thatincorporates the inter-costal pump described herein is draining fluidfrom a patient's pericardial region.

Other alternative uses are certainly possible as well. In general, afluid management system that incorporates the intercostal pump describedherein may be used to drain fluid to and from any combination of regionsin a patient's body with which fluid communication can be sufficientlyestablished with intercostal pump 110.

2. THE INTERCOSTAL PUMP

a. Intercostal Pump Design

FIG. 3A shows an exemplary cross-sectional schematic view of intercostalpump 110. As noted above, intercostal pump 110 is, generally, aresiliently flexible bulb. As such, the pump body, as well as any of theother various pump components, may be made of polyurethane, silicone,polyvinyl chloride, or latex rubber. Other materials are certainlypossible as well.

Intercostal pump 110 comprises a pump wall that encloses an interiorspace 330. For purposes of explanation, the pump wall is depicted asincluding upper wall 310 and lower wall 312. The distinction between anupper and lower wall is made for the purposes of clarity in explainingthe compression/decompression of intercostal pump 110 below, and shouldnot be interpreted as limiting intercostal pump 110 to comprise twodistinct pump walls.

Generally, pump wall 310 (312) may be of any thickness suitable toachieve desired flexibility of intercostal pump 110. The particularthickness of pump wall 310 (312) in a given embodiment may depend on,for example, the material of pump wall 310 (312) and the intended use(e.g., drainage function) of intercostal pump 110. In an embodiment,pump wall 310 (312) may be made of silicon and have a thickness of 1/32of an inch. In an embodiment, intercostal pump 110 may comprise siliconetubing having an inner diameter of ¼ of an inch and an outer diameter of5/16 of an inch. Other dimensions may be desirable as well.

Intercostal pump 110 further comprises inlet valve 320 and outlet valve322. Inlet valve 320 may be situated in the interior space 330 of thepump body in general proximity to inlet 130. Inlet valve 320 may be anysuitable one-way valve, and may, for example, be made of silicone. Inletvalve 320 is configured so as to preclude fluid movement from theinterior space 330 of intercostal pump 110 to inlet tube 130. At thesame time, inlet valve 320 is configured to allow fluid movement frominlet tube 130 to the interior space 330 of intercostal pump 110. Inother words, inlet valve 320 is in fluid communication with inlet 130 soas to provide for one-way fluid movement from inlet tube 130 to interiorspace 330 of intercostal pump 110.

Correspondingly, outlet valve 322 may be situated in the interior space330 of the pump body in general proximity to outlet 132. Outlet valve322 may be any suitable one-way valve, and may, for example, be made ofsilicone. Outlet valve 322 is configured so as to allow fluid movementfrom the interior space 330 of intercostal pump 110 to outlet tube 132.At the same time, outlet valve 322 is configured to prevent fluidmovement from outlet tube 132 to the interior space 330 of intercostalpump 110. In other words, outlet valve 322 is in fluid communicationwith outlet 132 so as to provide for one-way fluid movement frominterior space 330 of intercostal pump 110 to outlet tube 132.

It may be desirable to reinforce the outer perimeter of inlet valve 320and outlet valve 322 so that the compression/decompression ofintercostal pump 110 does not cause significant compression of, orundesirable wear to, inlet valve 320 and outlet valve 322. Suchreinforcement may be accomplished, for example, by using a relativelystiff, or non-flexible material, for the outer perimeter of inlet valve320 and outlet valve 322. Other examples may exist as well

Note that, although inlet valve 320 and outlet valve 322 are depicted assituated within the interior space 330 of intercostal pump 110,alternative placement of the valves may be desirable as well. Forexample, one of, or both of, inlet valve 320 and outlet valve 322 mightbe situated exterior to the pump body, perhaps within inlet tube 130 andoutlet tube 132, respectively. The particular placement of the valves isnot critical, so long as they sufficiently provide for one-way fluidflow into and out of intercostal pump 110.

b. Pump Operation

FIG. 3B shows an exemplary cross-sectional schematic view of intercostalpump 110 in a compressed state. In an exemplary embodiment, as shown, afirst force 340 acts on upper wall 310 causing upper wall 310 tocollapse in towards interior space 330. Correspondingly, a second force342 acts on lower wall 312 causing lower wall 312 to collapse in towardsinterior space 330. As described above, intercostal pump 110 isresiliently flexible and therefore, after being placed in a compressedstate as shown in FIG. 3B, intercostal pump 110 will return to anuncompressed state as shown in FIG. 3A when at least one of the firstforce 340 and the second force 342 are removed. In this way, intercostalpump 110 operates as a pump that, generally, draws fluid from its inlet130 to its outlet 132.

In use, intercostal pump 110 may be compressed as a result of a patientbreathing. More particularly, intercostal pump 110 may be compressed asa result of the natural movement of a patient's ribs during thebreathing cycle.

FIG. 3C shows an exemplary cross-sectional schematic view of intercostalpump 110 and tubes 120 and 122 having length extensions 160 and 162,respectively. FIG. 3C general shows tubes 120 and 122 as generallyflexible tubing that may be easily manipulated and/or shaped to take anyform or direction. However, in some embodiments it may be desirable fortubes 120 and 122 to be rigidly defined, to some extent, so that adesired shape or direction of the tubes may be maintained. For example,one of the tubes may be rigidly configured, shaped, or cast so that ithas a 90 degree bend upon leaving intercostal pump 110. Each of tubes120 and 122 may be configured to a similar 90 degree bend.Alternatively, the tubes may not have similar bends. As yet anotheralternative, the tubes may each have a bend of some other degree.

As shown in FIG. 4A, in use, intercostal pump 110 is placed between afirst rib 416 and a second rib 418. When the rib cage expands (uponinhaling), individual ribs 410, 412, 414, 416, and 418 separate andrelatively little force is exerted on intercostal pump 110. Therefore,intercostal pump 110 is in an uncompressed state.

However, as shown in FIG. 4B, when the rib cage contracts (uponexhaling), individual ribs 410, 412, 414, 416, and 418 move towards oneanother. As a result, a first force 340 and a second force 342 areexerted on intercostal pump 110 by first rib 416 and second rib 418respectively. Therefore, intercostal pump 110 is in a compressed state.

A normal adult takes about twelve breaths per minute. Therefore, in use,intercostal pump 110 may be compressed approximately twelve times perminute. Of course, this is only an approximation and may vary greatly. Aparticular compression rate is not critical to the functioning ofintercostal pump 110, though the rate at which fluid is pumped willobviously vary with the compression rate and amplitude of compression(i.e., degree of rib motion).

A normal adult exhibits approximately two millimeters of relative motionbetween ribs throughout the breathing cycle. Accordingly, the walls ofintercostal pump 110 may be compressed approximately two millimetersduring each breath. Of course, this is only an approximation and mayvary greatly.

A relevant consideration is that ribs are lined by soft tissue. The softtissue may be compressible itself and therefore, if any soft tissue isleft in place between intercostal pump 110 and either of first rib 416and second rib 418, the full extent of possible compression ofintercostal pump 110 may not be achieved. It may therefore be desirableto remove soft tissue at the point of contact of intercostal pump 110with either of first rib 416 and second rib 418.

Another relevant consideration is that ribs generally exhibit portionsthat are relatively cartilaginous, which portions may be relativelycompressible themselves. As a result, it may be desirable to placeintercostal pump 110 so as to be in contact with portions of first rib416 and second rib 418 exhibiting a relatively low amount of cartilage(i.e., a portion of the rib having a relatively high amount of bone, asopposed to cartilage, exposed).

Yet another relevant consideration is that it may be desirable tosituate intercostal pump 110 in such way that the amount of surface areaof intercostal pump 110 that is in contact with each of first rib 416and second rib 418 is maximized. In this way, intercostal pump 110 mayexperience a greater amount of compression. Therefore, it may bedesirable to situate intercostal pump 110 in a manner substantiallyparallel to first rib 416 and second rib 418 as opposed to thesubstantially perpendicular manner as generally indicated in FIGS. 4Aand 4B.

3. OTHER INTER-COSTAL PUMP BASED FLUID MANAGEMENT SYSTEM ARRANGEMENTS

As a patient breaths, the patients' pleural space expands and contracts.Accordingly, the pressure within the pleural space decreases andincreases, relatively. Such changes in the pressure within the pleuralspace may be used to activate a pump that is located within the pleuralspace. Thus, a pump within the pleural space may be activated by suchchanges in the pressure within the pleural space. These pressure changesmay activate a pump independently of, or in combination with, anyactivation caused by compression due to displacement of the patients'ribs as discussed above.

Similarly, as a patient breaths, the patients' abdomen expands andcontracts. Accordingly, the pressure within the abdomen decreases andincreases, relatively. Such changes in the pressure within the abdomenmay be used to activate a pump that is located within the abdomen. Thus,a pump within the abdomen may be activated by such changes in pressurewithin the abdomen.

As shown in FIG. 6, the inter-costal pump based fluid management systemmay include two pumps 110 and 610. According to such a system, pump 110may be placed within a patient's pleural space, perhaps within anintercostal region as discussed above. Pumps 110 and 610 may becommunicatively couple at points 602 and 604, respectively. Pumps 110and 610 may be communicatively coupled by an extendible tube, or a tubea given desired length. Pump 610 may then be placed within a patient'sabdomen. As a result, pump 110 may be activated by one or more ofcompression due to the patient's rib compression or pressure changewithin the patient's pleural space, and pump 610 may be activated bypressure change within the patient's abdomen.

Such a system including two pumps (such as that shown in FIG. 6) may becapable of achieving greater overall pump force than may be a systemincluding a single pump (such as shown in FIG. 1C.

4. EXEMPLARY METHODS a. First Exemplary Method

A method of draining a fluid from a first area of a person's body to asecond area of a person's body may be carried out with respect tointercostal-pump based fluid management system 100.

With reference to FIG. 5A and method 500, at step 502, intercostal pump110 is implanted in an intercostal space of a patient such that theintercostal pump may be compressed between first rib 416 and second rib418. Intercostal pump 100 may be implanted using known surgicaltechniques.

At step 504, fluid communication is established between a first area ofa patient and the inlet 130 of intercostal pump 110. For example, firsttube 120 may be extended from a patient's pleural cavity to inlet 130.

At step 506, fluid communication is established between a second area ofa patient and the outlet 132 of intercostal pump 110. For example,second tube 122 may be extended from outlet 132 to a patient'speritoneal cavity.

At step 508, intercostal pump 110 is periodically compressed. Forexample, intercostal pump 110 is compressed between first rib 416 andsecond rib 418 during a patient's breathing cycle.

b. Second Exemplary Method

With reference to FIG. 5B and method 550, at step 552, intercostal pump110 is decompressed. For example, intercostal pump 110 is initiallycompressed between first rib 416 and second rib 418 while a patient'sribs are in a contracted stated (i.e., the patient has previouslyexhaled). As the patient inhales, the rib cage is expanded and first rib416 and second rib 418 move away from one another. As a result,intercostal pump 110 is decompressed.

At step 554, intercostal pump 110 intakes fluid. That is, as a result ofdecompressing intercostal pump 110 at step 552, a pumping force drawsfluid into interior space 330 of intercostal pump 110.

At step 556, intercostal pump 110 is compressed. For example,intercostal pump 110 is compressed between first rib 416 and second rib418 as a result of the patient's rib cage being contracted (i.e., thepatient exhales). As the patient exhales, the rib cage is contracted andfirst rib 416 and second rib 418 move towards one another. As a result,intercostal pump 110 is compressed.

At step 558, intercostal pump 110 outputs fluid. That is, as a result ofcompressing intercostal pump 110 at step 556, a pumping force forcesfluid out of interior space 330 of intercostal pump 110.

5. CONCLUSION

Exemplary embodiments of an intercostal-pump based fluid managementsystem are described above. Those skilled in the art will understand,however, that changes and modifications may be made to the embodimentsdescribed without departing from the true scope and spirit of thepresent invention, which is defined by the claims.

The invention claimed is:
 1. A method comprising: implanting in anintercostal space of a person an intercostal pump such that theintercostal pump may be compressed between a first rib of the person anda second rib of the person, the intercostal pump comprising an inlet andan outlet; and establishing fluid communication (a) between a pleuralcavity of the person's body and the inlet with a first tube and (b)between the outlet and a peritoneal cavity of the person's body with asecond tube.
 2. The method of claim 1, further comprising: configuringthe intercostal pump for placement in the intercostal space so as to beactivated by being compressed by (a) the first rib at a first point ofcontact between the first rib and the intercostal pump and (b) thesecond rib at a second point of contact between the second rib and theintercostal pump.
 3. The method of claim 1, wherein the intercostal pumpis configured for placement in the intercostal space so as to beactivated by being compressed by (a) the first rib at a first point ofcontact between the first rib and the intercostal pump and (b) thesecond rib at a second point of contact between the second rib and theintercostal pump.
 4. The method of claim 1, wherein the intercostal pumpcomprises a first one-way valve in fluid-flow communication with theinlet and a second one-way valve in fluid-flow communication with theoutlet, the first one-way valve configured to preclude material movementfrom a bulb to the first tube, and the second one-way valve configuredto preclude material movement from the second tube to the bulb.
 5. Themethod of claim 1, further comprising: extending the first tube from thepleural cavity of the person to the inlet.
 6. The method of claim 1,further comprising: extending the second tube from the outlet to theperitoneal cavity of the person.
 7. The method of claim 1, furthercomprising: adjusting the length of one or each of the first tube or thesecond tube.
 8. The method of claim 1, further comprising: coating oneor more of the intercostal pump, the first tube, or the second tube inanticoagulation factors.
 9. The method of claim 1, wherein implanting inthe intercostal space of the person the intercostal pump such that theintercostal pump may be compressed between the first rib and the secondrib comprises implanting in the intercostal space of the person theintercostal pump such that an amount of surface area of intercostal pumpthat is in contact with each of the first rib and the second rib ismaximized.
 10. The method of claim 1, wherein the intercostal pumpcomprises one or more of polyurethane, silicone, polyvinyl chloride, orlatex rubber.
 11. The method of claim 1, wherein the first tubecomprises at least one fluid-inlet perforation along its surface. 12.The method of claim 1, wherein implanting in the intercostal space ofthe person the intercostal pump comprises implanting the intercostalpump such that the inlet and the first tube are each at least partiallydisposed on the interior of a rib cage of the person's body.
 13. Themethod of claim 1, wherein implanting in the intercostal space of theperson the intercostal pump comprises implanting the intercostal pumpsuch that the outlet and the second tube are at least partially disposedon the exterior of a rib cage of the person's body.
 14. The method ofclaim 1, wherein the intercostal pump comprises at least one resilientlyflexible pump wall.
 15. The method of claim 1, wherein one or each of anouter perimeter of the inlet and the outer perimeter of the outletcomprises a non-flexible material.
 16. The method of claim 1, furthercomprising: removing soft tissue from the intercostal space.
 17. Themethod of claim 1, wherein implanting in the intercostal space of theperson the intercostal pump comprises implanting the intercostal pumpsuch that it is substantially parallel to the first rib and the secondrib.
 18. The method of claim 1, wherein implanting in the intercostalspace of the person the intercostal pump comprises implanting theintercostal pump such that it is substantially perpendicular to thefirst rib and the second rib.
 19. A method comprising: implanting in anintercostal space of a person an intercostal pump such that theintercostal pump may be compressed between a first rib of the person anda second rib of the person, the intercostal pump comprising an inlet andan outlet, wherein the intercostal pump comprises silicone, and whereinthe first tube comprises at least one fluid-inlet perforation along itssurface; and establishing fluid communication (a) between a pleuralcavity of the person's body and the inlet with a first tube and (b)between the outlet and a peritoneal cavity of the person's body with asecond tube.
 20. A method comprising: implanting in an intercostal spaceof a person an intercostal pump such that the intercostal pump may becompressed between a first rib of the person and a second rib of theperson, the intercostal pump comprising an inlet and an outlet; andestablishing fluid communication between (a) a pleural cavity of theperson's body and the inlet with a first tube and (b) between the outletand a peritoneal cavity of the person's body with a second tube, whereinimplanting in the intercostal space of the person the intercostal pumpcomprises implanting the intercostal pump such that (a) the inlet andthe first tube are each at least partially disposed on the interior of arib cage of the person's body and (b) the outlet and the second tube areat least partially disposed on the exterior of a rib cage of theperson's body.